The Linux Networking Architecture [Electronic resources] نسخه متنی

Appendix E. Example for a Network-Layer Protocol

/**********************************************************
* Example for a network-layer protocol
* Compile:
* gcc -I/lib/modules/'uname -r'/build/include -c file.c
**********************************************************/
#ifndef _KERNEL_
#define _KERNEL_
#endif
#ifndef MODULE
#define MODULE
#endif
#include <linux/module.h>
#include <linux/version.h>
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/netdevice.h>
MODULE_AUTHOR("Test Author (fixme@Linux-netzwerkarchitektur.de)");
MODULE_DESCRIPTION("Module with a layer-3 test protocol");
#define TEST_PROTO_ID 0x1234
int test_pack_rcv(struct sk_buff *skb, struct net_device *dev, struct
packet_type *pt);
static struct packet_type test_protocol =
{
_constant_htons(TEST_PROTO_ID),
NULL,
test_pack_rcv,
      (void *) 1,
NULL
};
int test_pack_rcv(struct sk_buff *skb, struct net_device *dev, struct
packet_type *pt)
{
printk(KERN_DEBUG "Test protocol: Packet Received with length: %u\n",
skb->len);
return skb->len;
}
int init_module(void)
{
dev_add_pack(&test_protocol);
return 0;
}
void cleanup_module(void)
{
dev_remove_pack(&test_protocol);
}